The laser scalpel and the laser coagulator are representative in laser medicine. However the biostimulative effect of laser with low power is getting the focus of attention, since acceleration of wound healing has been proved by laser radiation. Recently laser acupuncture was initiated as an unique therapeutic application in Europe and China. In Japan the authors have developed YAG laser acupun...

A parallel Hopscotch algorithm for the simulation of semiconductor laser arrays which overlaps the computations and communications is presented. The method uses a Lax-Wendroff scheme for the hyperbolic part of the operators and allows to obtain near-to-perfect speed-ups on MIMD computers. Numerical experiments indicate that semiconductor laser arrays exhibit a rich dynamic behavior ranging from...

The output spectrum of both gas and semiconductor lasers usually contains more than one frequency. Multimode operation in gas versus semiconductor lasers arises from different physics. In gas lasers, slow equilibration of the electron populations at different energies makes each frequency an independent single-mode laser. The slow electron diffusion in semiconductor lasers, combined with the sp...

This review focuses on theoretical foundations, experimental implementation and an overview of experimental results of the thermoreflectance spectroscopy as a powerful technique for temperature monitoring and analysis of thermal processes in semiconductor lasers. This is an optical, non-contact, high spatial resolution technique providing high temperature resolution and mapping capabilities. Th...

Approaches are discussed for a direct solar-pumped semiconductor laser. Efficiencies of 35% should be achievable, an order of magnitude better than the efficiency achieved by other solar-pumped lasers. The output wavelength of a semiconductor laser will be well matched to the optimum conversion efficiency of a solar cell of the same material. Solar pumped semiconductor lasers are thus an excell...

Efficient and reliable models for semiconductor distributed feedback (DFB) lasers design and optimization are highly desirable. An innovative dynamic model for accurate simulations of DFB lasers is proposed in this paper. The developed algorithm is based on a system of coupled partial differential equations which is solved by the finite element method (FEM). No approximation is assumed and obta...

A room temperature operating Vertical External Cavity Surface Emitting Laser is applied around 1550 nm to intracavity laser absorption spectroscopy analyzed by timeresolved Fourier transform interferometry. At an equivalent pathlength of 15 km, the high resolution spectrum of the semiconductor disk laser emission covers 17 nm simultaneously. A noise equivalent absorption coefficient at one seco...

The phase modulation (PM) and amplitude modulation (AM) of optical signals can be achieved using a direct-modulated (DM) optical injection-locked (OIL) semiconductor laser. We propose and theoretically analyze a simple method to extract the phase component of a PM signal produced by a DM-OIL semiconductor laser. The pure AM component of the combined PM–AM signal can be isolated by square-law de...

This review focuses on theoretical foundations, experimental implementation and an overview of experimental results of the thermoreflectance spectroscopy as a powerful technique for temperature monitoring and analysis of thermal processes in semiconductor lasers. This is an optical, non-contact, high spatial resolution technique providing high temperature resolution and mapping capabilities. Th...

Langevin noise leads to inhibition of the temporal synchronization of the pulse oscillations from a gain-switched multimode semiconductor laser, resulting in the power reduction in optical beat detection. In this paper, the degree of the temporal synchronization of the pulse oscillations was examined by numerically estimating the output energy in THz time-domain spectroscopy (THz-TDS) using mul...